JP4609674B2 - Image processing system, display device, program, and information storage medium - Google Patents

Description

  The present invention relates to an image processing system, a display device, a program, and an information storage medium for performing color adjustment.

As described in Japanese Patent Application Laid-Open No. 2007-96612, there is a method of changing the RGB color space to the HSV color space as a method of adjusting the color of the image. In this method, the adjustment affects all colors. Will reach. Japanese Patent Application Laid-Open No. 2007-96612 proposes a method of adjusting the hue, saturation, and brightness for each of RGBCMY. Specifically, as a method for adjusting the hue, the method disclosed in Japanese Patent Application Laid-Open Nos. 2007-96612 and 2002-330298 moves a specific color (for example, R color, B color, etc.) to an adjacent color. Is used.
JP 2007-96612 A JP 2002-330298 A

  However, for example, if one of RGB hues is adjusted, it approaches W (white), so the brightness increases. If one of CMY hues is adjusted, it approaches K (black), so the brightness decreases. Therefore, it becomes difficult to adjust to the target color (hue, lightness, saturation). In general, when the adjustment to increase the brightness is performed, the image becomes whitish and the saturation is decreased. Therefore, it is difficult to adjust the target color.

  In addition, in order to change the RGB color space to the HSV color space, the Lab color space, or the like, complicated calculations are required, and the efficiency of image processing is reduced. For example, in the case of a color space used to match the color of an image on a display device and the color of an image output by a printer, the RGB color space needs to be changed to information indicating a device independent color such as a Lab space. In the case of a display device, it is not necessary to be aware of device-independent colors, and changing the RGB color space to a Lab color space or the like is inefficient.

  An object of the present invention is to provide an image processing system, a display device, a program, and an information storage medium that can be easily adjusted to a target color.

  In order to solve the above problems, an image processing system according to the present invention includes a hue of at least one of the reference colors including a plurality of RGB reference colors and a plurality of CMY reference colors in a color space. An update unit that updates the color space information indicating the color space by rotating the selection reference color about a straight line connecting white and black in the color space as a rotation axis based on the adjustment information indicating that the color space is adjusted, and And a correction unit that corrects the input image signal based on the color space information.

  A display device according to the present invention includes the image processing system and a display unit that displays an image based on the input image signal corrected by the correction unit.

  Further, the program according to the present invention causes the computer to adjust the hue of at least one of the reference colors including a plurality of RGB reference colors and a plurality of CMY reference colors in the color space. An update unit that updates the color space information indicating the color space by rotating the selection reference color about a straight line connecting white and black in the color space as a rotation axis based on the adjustment information indicating the color space, and the color space information Based on this, it is made to function as a correction unit for correcting the input image signal.

  An information storage medium according to the present invention is a computer-readable information storage medium and stores the above program.

  According to the present invention, when adjusting the hue, the image processing system or the like adjusts the hue by updating the color space information by rotating and moving the selection reference color about the straight line connecting white and black as the rotation axis. Even in such a case, the target color can be adjusted without changing the brightness.

  The image processing system according to the present invention adjusts the brightness of at least one of the reference colors including a plurality of reference colors of RGB and a plurality of reference colors of CMY in the color space. An update unit that updates the color space information indicating the color space by moving the reference color on a straight line connecting the reference color and black or white in the color space based on the adjustment information to be displayed; and And a correction unit for correcting the input image signal.

  A display device according to the present invention includes the image processing system and a display unit that displays an image based on the input image signal corrected by the correction unit.

  In addition, the program according to the present invention causes the computer to adjust the brightness of at least one of the reference colors including a plurality of RGB reference colors and a plurality of CMY reference colors in a color space. An update unit that updates the color space information indicating the color space by moving the reference color on a straight line connecting the reference color and black or white in the color space based on the adjustment information indicating the color space, and the color space information Based on the above, it is made to function as a correction unit for correcting the input image signal.

  An information storage medium according to the present invention is a computer-readable information storage medium and stores the above program.

  According to the present invention, when adjusting the brightness, the image processing system or the like adjusts the brightness by updating the color space information by moving the reference color on a straight line connecting the reference color and black or white. Even in this case, the target color can be adjusted without changing the saturation.

  In addition, the color space is a solid that has each reference color, black, and white as vertices, and the update unit is configured so that the rotation axis coincides with a straight line that connects black before rotation and a predetermined reference color. The color space information may be updated based on an inverse matrix of a rotation matrix indicating that the image is rotated.

  According to this, when rotating the reference color to adjust the hue, the image processing system or the like can obtain the value more efficiently by performing the calculation based on the inverse matrix of the rotation matrix.

  The adjustment information includes information indicating that the brightness of at least one of the reference colors in the reference color group is adjusted, and the correction unit is information indicating that the brightness of the reference color is adjusted. Based on this, the color space information may be updated by moving the reference color on a straight line connecting the reference color and black or white in the color space.

  According to this, when adjusting the brightness, the image processing system or the like adjusts the brightness by updating the color space information by moving the reference color on a straight line connecting the reference color and black or white. Even in such a case, the target color can be adjusted without changing the saturation.

  The adjustment information includes information indicating that the saturation of at least one of the reference colors in the reference color group is adjusted, and the update unit indicates that the saturation of the reference color is adjusted. Based on the information, the color space information may be updated by moving the reference color on a straight line that is orthogonal to the straight line connecting black and white in the color space and passes through the reference color.

  According to this, when adjusting the saturation, the image processing system or the like can adjust the target color without changing the lightness or hue.

  The color space may be an RGB color space, and the correction unit may adjust the color of an image displayed on a display device by correcting the input image signal.

  According to this, since the image processing system or the like does not need to perform color space conversion or the like, the image color can be adjusted more efficiently.

  In addition, an adjustment information input unit that inputs the adjustment information is included, the display unit displays an adjustment image for adjusting hue, brightness, and saturation for each reference color, and the adjustment information input unit includes the adjustment information input unit. The adjustment information may be input according to the adjustment in the adjustment image.

  According to this, the image processing system or the like can generate a color according to the purpose of the user when the adjustment information is input according to the input of the user, for example.

  Embodiments in which the present invention is applied to a projector having an image color adjustment function will be described below with reference to the drawings. In addition, the Example shown below does not limit the content of the invention described in the claim at all. In addition, all the configurations shown in the following embodiments are not necessarily essential as means for solving the invention described in the claims.

  FIG. 1 is a functional block diagram of a projector 100 in the present embodiment. The projector 100 receives an adjustment information input unit 110 that inputs adjustment information related to adjustment of brightness and the like, a storage unit 130, an update unit 120 that updates data in the storage unit 130, and an image signal (for example, an RGB signal). The image signal input unit 150 is configured to include an input image signal input unit 150, a correction unit 140 that corrects the image signal, and a projection unit 190 that projects an image based on the corrected image signal. The projection unit 190 is a type of display unit that displays an image, and the projector 100 is a type of display device.

  In addition, the storage unit 130 stores color space information 132 indicating a color space, image data 134 for generating an adjustment image described later, and the like. In this embodiment, the color space is an RGB color space (also referred to as an RGB space).

  Note that these units may be implemented using, for example, the following hardware. For example, the adjustment information input unit 110 includes a remote controller (remote controller), a button, the update unit 120 includes a CPU, the storage unit 130 includes a RAM and an HDD, the image signal input unit 150 includes an image signal input terminal, and the like. The correction unit 140 may be mounted using an image processing circuit or the like, and the projection unit 190 may be mounted using a lamp, a liquid crystal panel, a liquid crystal driving circuit, a projection lens, or the like.

  In addition, the computer included in the projector 100 may implement functions such as the update unit 120 by reading a program from the information storage medium 200. As such an information storage medium 200, for example, a CD-ROM, DVD-ROM, ROM, RAM, HDD or the like can be applied, and the program reading method may be a contact method or a non-contact method. Good.

  Next, a procedure for adjusting the color of an image using the update unit 120 will be described. FIG. 2 is a flowchart showing the procedure for adjusting the color of the image in this embodiment. First, the correction unit 140 generates an adjustment image using the image data 134, and the projection unit 190 projects the adjustment image (step S1).

  FIG. 3 is a diagram illustrating the first adjustment image 300 in the present embodiment. FIG. 4 is a diagram showing a second adjustment image 302 in the present embodiment. For example, the adjustment image 300 is projected by the projector 100 when the user performs an operation of displaying the adjustment image 300 using the remote controller.

  The adjustment image 300 is an adjustment state of hue, saturation, and lightness of each of the reference color groups including R, G, and B that are RGB reference colors and C, M, and Y that are CMY reference colors. It is an image which shows. The user moves the selection cursor in the adjustment image 300 by pressing the up and down arrow keys on the remote control, selects the reference color to be adjusted, and presses the “Select” key on the remote control to determine the reference color. When the “Select” key is pressed, an adjustment image 302 for adjusting the color of the reference color is projected by the projector 100.

  The adjustment image 302 is an image for adjusting the hue, saturation, and brightness of the selected reference color. The user moves the selection cursor in the adjustment image 302 by pressing the up and down arrow keys on the remote control, selects one of hue, saturation, and brightness, and presses the left and right arrow keys on the remote control. Change the setting value. For example, in the example shown in FIG. 4, the setting value of the hue of R is changed from −64 to −63. The adjusted image is separated into the adjusted image 300 and the adjusted image 302, so that the user can easily select and adjust with only the up / down / left / right arrow keys. The adjusted images 300 and 302 may be, for example, OSD (On Screen Display) images.

  The adjustment information input unit 110 inputs operation information (adjustment information) from the remote controller (step S2), and the update unit 120 updates the color space information 132 and the like based on the adjustment information (step S3). Note that the setting values for each reference color are stored in the storage unit 130 as part of the image data 134.

  The adjustment information input unit 110 determines whether or not the adjustment is completed by determining whether or not the “Menu” key of the remote controller is pressed (step S4). The projector 100 repeatedly executes the processes in steps S2 to S4 until the adjustment is completed. Note that the user can return to the adjustment image 300 and adjust other reference colors by pressing the “ESC” key on the remote controller while the adjustment image 302 is displayed.

  Here, a method for updating the color space information 132 will be described more specifically. First, hue adjustment will be described. FIG. 5 is a diagram illustrating an example of the color space in the initial state. For example, the normal RGB color space is in the state shown in FIG. 5 and has a cubic shape with K (black) as the origin and R, G, B, C, M, Y, K, and W (white) as vertices. It is. In addition, the cube is arranged in contact with each axis, with the straight line passing through the vertex KR as the x axis, the straight line passing through the vertex KG as the y axis, and the straight line passing through the vertex KB as the z axis.

  FIG. 6 is a diagram illustrating an example of the color space in a rotated state. In the present embodiment, the correction unit 140 performs an operation on the cube shown in FIG. 5 while rotating the cube so that the straight line passing through the vertex KB coincides with the z-axis. In the state shown in FIG. 6, RGB regular triangles are arranged at the position of one third of the line segment KW, and CMY regular triangles are arranged at the position of two thirds of the line segment KW.

The calculation for rotating the straight line passing through the vertex KB so as to coincide with the z-axis is represented by a rotation matrix A. Specifically, the rotation matrix A is
become.

In order to return the coordinates shown in FIG. 6 to the coordinates shown in FIG. 5, an inverse matrix B of the rotation matrix A may be used. The inverse matrix B is
become.

  FIG. 7 is a schematic diagram of a color space during hue adjustment. For example, when the cube shown in FIG. 6 is viewed from above (the direction opposite to the z direction), the shape is as shown in FIG. For example, if the hue adjustment value is H, R is in a state where H = 0 is a default value, H = 1 matches Y, and H = −1 matches M. Since the angle RWY and the angle RWM are each 60 degrees, the angle θ = 60H indicating the angle to be adjusted.

  For example, in the adjustment image 302, the hue is adjusted with a value from −64 to 64, but the hue adjustment value H is adjusted with a value from −1 to 1. That is, the correction unit 140 converts the hue setting value set in the image data 134 to obtain the hue adjustment value H.

  Next, the saturation adjustment will be described. FIG. 8 is a schematic diagram of a color space during saturation adjustment. The saturation adjustment value is S, and S can be adjusted in the range of 0 to 2. S = 1 is the default value, and when S = 2, the saturation is doubled. That is, as S increases, the distance from the z axis (WK axis) increases. In the adjusted image 302, the saturation is adjusted with a value from −64 to 64. Therefore, the correction unit 140 converts the saturation setting value set in the image data 134. A saturation adjustment value S is obtained.

  Next, brightness adjustment will be described. FIG. 9 is a schematic diagram of a color space during brightness adjustment. Assume that the brightness adjustment value is V, and V can be adjusted in the range of 0 to 2. As shown in FIG. 9, in the case of RGB, the V value is a magnification of the distance from the vertex K, V = 1 is the default value, and coincides with the vertex K when V = 0, and the brightness is when V = 2. Doubled.

  In the case of CMY, since the amount of change is too large when the magnification is used as it is, the brightness is adjusted to be half the brightness when V = 0 and 1.5 times the brightness when V = 2. In the adjusted image 302, the lightness is adjusted with a value from −64 to 64. Therefore, the correction unit 140 converts the lightness setting value set in the image data 134 to change the lightness. An adjustment value V is obtained.

Next, a case where all of hue, saturation, and brightness are adjusted will be described. FIG. 10 is a schematic diagram of a color space when adjusting hue, brightness, and saturation. The coordinates of R in the state shown in FIG. 6 are (√6 / 3, 0, √3 / 3). A point obtained by rotating R by θ degrees around the z axis is R ′, R ′, a point obtained by multiplying the distance from the z axis by S, and R ″ and R ″ are multiplied by V based on the origin K. Let the point be R ′ ″. The coordinates of R '''are
become.

When the coordinates of R '''are restored to the coordinates before rotation,
become.

Therefore, when the vertex R in the color space is adjusted, the RGB value of the vertex R after the adjustment is
become.

  Further, when the vertex G in the color space is adjusted, the RGB value of the vertex G after the adjustment is such that the R value of the vertex R in the above formula becomes the G value, the G value becomes the B value, and the B value becomes the R value. Become. In the RGB value of the vertex B after adjustment, the R value of the vertex R in the above formula becomes the B value, the G value becomes the R value, and the B value becomes the G value. When any one of the reference colors is adjusted, only the position of the reference color (for example, the vertex R) is changed, and the positions of the other reference colors (vertices) are not changed.

  Also, the CMY arithmetic expression is that the coordinate value of the vertex C in the state where the cube is changed with the rotation matrix A so that the WK axis is vertical is (−√6 / 3, 0, 2√3 / 3). Can be calculated in the same manner as RGB. However, as described above, the lightness magnification is not the value of V (0 to 2) itself, but is adjusted to be 0.5 to 1.5 times, and thus becomes (V + 1) / 2 times.

Therefore, when the vertex C in the color space is adjusted, the RGB value of the vertex C after the adjustment is
become.

  Further, when the vertex M in the color space is adjusted, the RGB value of the vertex M after the adjustment is such that the R value of the vertex C in the above formula becomes the G value, the G value becomes the B value, and the B value becomes the R value. Become. In the RGB value of the vertex Y after adjustment, the R value of the vertex C in the above formula becomes the B value, the G value becomes the R value, and the B value becomes the G value.

  As described above, the update unit 120 can update the color space information 132 based on the setting value indicated by the image data 134. The substance of the color space information 132 may be a table (for example, a lookup table) or a function value.

  In a state where the adjustment and the update of the color space information 132 are completed, the image signal input unit 150 inputs the image signal (step S5), and the correction unit 140 corrects the input image signal with reference to the color space information 132. (Step S6).

  When correcting the color that is not defined in the color space information 132, the correction unit 140 performs a linear interpolation operation using the color value defined in the color space information 132, for example, thereby performing an input image. Correct the signal. Further, when the correction results in exceeding the color gamut, for example, the correction unit 140 determines the corrected color value as a close color value within the color gamut.

  Based on the image signal corrected by the correction unit 140, the projection unit 190 forms an image on the liquid crystal panel and projects the image (step S7).

  As described above, according to the present embodiment, when adjusting the hue, the projector 100 updates the color space information 132 by rotating the selection reference color about the straight line connecting white and black as the rotation axis. Thus, even when the hue is adjusted, the target color can be adjusted without changing the brightness.

  Further, according to the present embodiment, the projector 100 obtains a value more efficiently by performing an operation based on the inverse matrix B of the rotation matrix A when rotating the reference color in order to adjust the hue. be able to.

  Further, according to the present embodiment, when adjusting the brightness, the projector 100 updates the color space information 132 by moving the reference color on a straight line connecting the reference color and black or white, thereby adjusting the brightness. Even when the color is adjusted, it is possible to adjust to the target color without changing the saturation.

  In addition, according to the present embodiment, when adjusting the saturation, the projector 100 adjusts the saturation by changing the distance from the WK axis, thereby changing the target color without changing the lightness or hue. Can be adjusted.

  Further, according to the present embodiment, the projector 100 corrects the RGB signal by using the RGB color space, so that it is not necessary to perform color space conversion or the like, so that the color of the image can be adjusted more efficiently. Can do.

  Furthermore, according to the present embodiment, the projector 100 can input adjustment information according to the user's input by using the adjustment images 300 and 302, and thus generates a color according to the user's purpose. Can do.

  In addition, application of this invention is not limited to the Example mentioned above, A various deformation | transformation is possible. For example, the configurations of the adjustment images 300 and 302 are not limited to the configurations illustrated in FIGS. For example, all the reference colors may be displayed and adjusted with one image. Further, the set values in the adjustment images 300 and 302 may be matched with the internal adjustment values. Further, the projector 100 may display a sample image or the like when the adjustment is performed, and correct and display the color of the sample image according to the adjustment every time the adjustment is performed.

  The plurality of RGB reference colors are not limited to the three colors R, G, and B, and may be two colors or four or more colors. The plurality of CMY-based reference colors are not limited to the three colors C, M, and Y, and may be two colors or four or more colors. Further, the reference color may be an intermediate color of the reference colors such as RGB described above.

  Further, the color space is not limited to the RGB color space, and an arbitrary color space can be adopted according to the type of the input image signal.

  The projector 100 is not limited to a liquid crystal projector, and may be a projector using a DMD (Digital Micromirror Device), for example. DMD is a trademark of Texas Instruments Incorporated. Further, the functions of the projector 100 may be distributed and implemented in a plurality of devices (for example, a PC and a projector).

  The display device to which the present invention can be applied is not limited to the projector 100, and may be a television, a liquid crystal monitor, a PDA, a mobile phone, or the like. In addition, the electronic apparatus in which the image processing system of the present invention can be mounted is not limited to a display device, and the image processing system of the present invention can be mounted in various electronic apparatuses that input, correct, and output image signals. .

It is a functional block diagram of the projector in a present Example. It is a flowchart which shows the adjustment procedure of the color of the image in a present Example. It is a figure which shows the 1st adjustment image in a present Example. It is a figure which shows the 2nd adjustment image in a present Example. It is a figure which shows an example of the color space of an initial state. It is a figure which shows an example of the color space of the state rotated. It is a schematic diagram of the color space at the time of hue adjustment. It is a schematic diagram of the color space at the time of saturation adjustment. It is a schematic diagram of the color space at the time of brightness adjustment. It is a schematic diagram of the color space when adjusting hue, lightness, and saturation.

Explanation of symbols

  100 Projector (Display Device), 110 Adjustment Information Input Unit, 120 Update Unit, 130 Storage Unit, 132 Color Space Information, 134 Image Data, 140 Correction Unit, 190 Projection Unit (Display Unit), 200 Information Storage Medium, 300, 302 Adjustment image

Claims (7)

Based on the adjustment information indicating that the brightness of an adjustment target reference color that is one reference color among reference color groups including a plurality of RGB reference colors and a plurality of CMY reference colors in the color space is adjusted. An update unit that updates the color space information indicating the color space by moving the adjustment target reference color on a straight line connecting the adjustment target reference color and black in the color space;
A correction unit that corrects an input image signal based on the color space information;
Including
In the update unit, when the reference color to be adjusted is the CMY reference color, the amount of change in brightness with respect to the same brightness adjustment value is relatively small compared to the case where the reference color is RGB. Updating the color space information,
Image processing system. The image processing system according to claim 1 ,
The adjustment information includes information indicating that the saturation of the adjustment target reference color is adjusted,
The update unit is a straight line that is orthogonal to a straight line connecting black and white in the color space and passes through the adjustment target reference color based on information indicating that the saturation of the adjustment target reference color is adjusted. An image processing system, wherein the color space information is updated by moving the adjustment target reference color on the top. The image processing system according to claim 1,
The color space is an RGB color space,
The image processing system, wherein the correction unit adjusts a color of an image displayed on a display device by correcting the input image signal. The image processing system according to any one of claims 1 to 3 ,
A display unit for displaying an image based on the input image signal corrected by the correction unit;
A display device comprising: The display device according to claim 4 ,
An adjustment information input unit for inputting the adjustment information;
The display unit displays an adjustment image for adjusting hue, brightness, and saturation for each reference color,
The display device characterized in that the adjustment information input unit inputs the adjustment information in accordance with the adjustment in the adjustment image. Computer
Based on the adjustment information indicating that the brightness of an adjustment target reference color that is one reference color among reference color groups including a plurality of RGB reference colors and a plurality of CMY reference colors in the color space is adjusted. An update unit that updates the color space information indicating the color space by moving the adjustment target reference color on a straight line connecting the adjustment target reference color and black in the color space;
Based on the color space information, function as a correction unit for correcting the input image signal,
In the update unit, when the reference color to be adjusted is the CMY reference color, the amount of change in brightness with respect to the same brightness adjustment value is relatively small compared to the case where the reference color is RGB. Updating the color space information,
program. A computer-readable information storage medium storing the program according to claim 6 .